--- parsec-2.1-orig/pkgs/apps/raytrace/src/RTTL/common/MapOptions.hxx	2013-01-25 13:39:06.000000000 +0100
+++ parsec-2.1/pkgs/apps/raytrace/src/RTTL/common/MapOptions.hxx	2013-01-25 13:31:57.000000000 +0100
@@ -24,6 +24,7 @@
 #define ACCESS_FILE _access
 #define COMPPARE_STRINGS_IGNORE_CASE stricmp
 #else
+#include <unistd.h>
 #define ACCESS_FILE access
 #define COMPPARE_STRINGS_IGNORE_CASE strcasecmp
 #endif
